https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105774
Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Summary|Bogus overflow in constant |Bogus overflow in constant |expression with char++ |expression with signed | |char++ Known to fail| |5.1.0 --- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Here is a C++14 testcase (lambdas were not constexpr in C++14) which shows the issue has been there since GCC 5 (which didn't have C++17 support): constexpr signed char f(void){ signed char x = 127; return ++x; } int main() { constexpr auto _ = f(); }